Manual of Clinical Paramedic Procedures by Pete Gregory, Ian Mursell (z-lib.org)

Infection control Chapter 12 Disposable aprons Several studies show the potential for uniforms to become contaminated.25–27 None of these studies were undertaken in the community setting but it is reasonable to suggest that the risk of contamination in the out-of-hospital setting is likely to be no lower than the in-hospital setting. Two of these studies25,26 suggest the need for a clean uniform to be worn each shift, which may not be achievable in the community setting given that jackets and fleeces are frequently worn in cooler weather. The routine use of aprons is not advocated,15 but plastic aprons are recommended for use when there is a likelihood of contamination with blood, body fluids, excretions or secretions (excluding sweat), or when close contact with the patient, equipment or materials may lead to contamination of clothing.23,24 Care should be taken to store disposable aprons away from potential sources of contamination prior to use and should be used once only. Full body gowns need only be worn where there is a risk of extensive splashing of body fluids, blood, secretions and excretions; e.g. serious trauma.23,24 Recommendations4 • Disposable plastic aprons should be worn when there is a risk that clothing may become exposed to blood, body fluids, excretions or secretions, with the excep- tion of sweat. • Plastic aprons should be worn for only one procedure or episode of patient care; they should then be disposed of as clinical waste. • Full-body, fluid-repellent gowns should be worn where there is a risk of extensive splashing of body fluids, blood, secretions or excretions onto the skin or clothing of a healthcare practitioner. Eye, mouth and nose protection There is no robust evidence to support the use of surgical face-masks to protect the patient during routine procedures such as wound dressings.15,23 In situations where protection is required, e.g., HIV-related or multiple drug-resistant tuberculosis, stan- dard surgical masks do not provide effective protection and specialised equipment such as a particulate filter respiratory mask should be worn.15,23,28 Recommendations4 • Face masks and eye protection must be worn where there is a risk of splashing of body fluids, blood, secretions or excretions into the face and eyes. • When clinically indicated, respiratory protective equipment must be used. Environmental cleanliness Maintaining a clean ambulance and equipment is essential, not only for reducing the risk of exposing patients to healthcare acquired infections, but also because it engenders confidence in the patients being conveyed by the ambulance service. In 235

Chapter 12 Infection control 2006 the Department of Health introduced the Standards for Better Health,30 which states the following: Healthcare organisations keep patients, staff and visitors safe by having systems to ensure that: • The risk of health care acquired infection to patients is reduced, with particular emphasis on high standards of hygiene and cleanliness, achieving year-on-year reductions in MRSA. • All risks associated with the acquisition and use of medical devices are minimised. • All reusable medical devices are properly decontaminated prior to use and that the risks associated with decontamination facilities and processes are well managed. • Medicines are handled safely and securely. • The prevention, segregation, handling, transport and disposal of waste is prop- erly managed so as to minimise the risks to the health and safety of staff, patients, the public and the safety of the environment. Keeping the vehicle clean is everybody’s responsibility. This section does not endeavour to set policies for Ambulance Trusts, as these policies should be developed by managers utilising the National Patient Safety Agency Framework for setting and measuring performance outcomes in ambulance trusts.29 Written local policies should be available for cleaning, decontamination, disinfection and sterilisation of all equipment and vehicles,31 and should be followed rigorously by ambulance crews. Recommendations31 • Ambulance interiors should be thoroughly cleaned on a weekly basis. • All equipment used for patient treatment should be cleaned using detergent wipes or soap and water then either air dried or wiped with clean paper towels after EVERY patient. • Extra attention must be given to items soiled with blood and/or body fluids; these should be decontaminated with detergent after cleaning. • Additional cleaning is required following transportation of a patient suffering from diarrhoea as the infection status may be unknown. The vehicle interior, including walls and floors, and all equipment used to treat the patient must first be cleaned with soap and water and then disinfected with a chlorine-based fluid. Clostridium difficile is only removed when both soap and water and disinfectant are used in the above order. • Ambulance stretcher beds should have linen changed after EVERY patient and the stretcher should be wiped down with detergent wipes or soap and water then air-dried or wiped dry with clean paper towels after EVERY patient. • Where contaminated with blood and/or body fluids, a chlorine-based detergent should be used after it has been cleaned with soap and water or detergent wipes. • Pillows should have a plastic cover, which should be wiped with a detergent wipe before a clean pillowcase is fitted. Pillowcases must be changed after EVERY patient. 236

Infection control Chapter 12 Chapter Key Points 1. Effective handwashing reduces the number of pathogens present on the hands. 2. There is no compelling evidence to favour one handwashing agent over another – in the prehospital environment ease of use may be the over-riding factor. 3. The thumbs and finger tips are the most commonly missed areas during hand- washing. 4. There is expert agreement that gloves play a role in protecting the hands from contamination, and reducing the risk of transmission of micro-organisms to both patient and practitioner. 5. The decision to use PPE and the level of PPE is based upon an assessment of the anticipated risk of transmission of micro-organisms to the patient, and the risk of exposure to body fluid during patient management. 6. Vehicle cleaning is the responsibility of everybody, not just of cleaning staff. 7. Written local policies should be available for cleaning, decontamination, disinfection and sterilisa- tion of all equipment and vehicles. References and Further reading See Chapter 13 for management of sharps and needlestick injuries, and for swabbing prior to injection or intravenous cannulation. Perry C. Infection Prevention and Control. Oxford: Blackwell, 2007. Ambulance Service Association. National Guidance and Procedures for Infection Prevention and Control. London: Ambulance Service Association, 2004. National Patient Safety Agency. The national specifications for cleanliness in the NHS: A framework for setting and measuring performance outcomes in ambulance trusts. London: NPSA, 2008. 1 Hart S. Using an aseptic technique to reduce the risk of infection. Nurs Stand 2007;21(47):43– 48. 2 Crow S. Asepsis: an indispensible part of the patient’s care plan. Crit Care Nurse Quest 1989;11(4):11–15. 3 Department of Health. Saving Lives: the Delivery Programme to Reduce Healthcare Associ- ated Infections (HCAI) Including MRSA. London: The Stationery Office, 2005. 4 National Institute for Health and Clinical Excellence (NICE). Infection control Prevention of healthcare-associated infection in primary and community care. London: NICE, 2003. 5 Department of Health. Clean, Safe Care: Reducing Infections and Saving Lives. London: Department of Health Publications, 2008. 6 Sutcliffe A. Press release: NICE launches new clinical guideline on prevention of healthcare associated infections in primary and community care. London: NICE, 2003. 7 Haley RW, Culver DH, White JW, Morgan WM, Grace TG, Munn VP, Hooton TM. The Efficacy of Infection Surveillance and Control Programs in Preventing Nosocomial Infections in US Hospitals. Am J Epidemiol 1985;121(2):182–205. 8 Ryan MAK, Christian RS, Wohlrabe J. Handwashing and respiratory illness among young adults in military training. Am J Prevent Med 2001;21(2):79–83. 237

Chapter 12 Infection control 9 Fendler EJ, Ali Y, Hammond BS, Lyons MK, Kelley MB, Vowell NA. The impact of alcohol hand sanitizer use on infection rates in an extended care facility. Am J Infect Control 2002;30(4):226–233. 10 Gould D, Gammon J, Donnelly M, Batiste L, Ball E, De Melo AMSC et al. Improving hand hygiene in community healthcare settings: the impact of research and clinical collaboration. J Clin Nurs 2000;9(1):95–102. 11 Pittet D, Dharan S, Touveneau S, Sauvan V, Perneger T. Bacterial contamination of the hands of hospital staff during routine patient care. Arch Intern Med 1999;159(8):821–826. 12 Boyce JM, Pittet D. Guideline for Hand Hygiene in Healthcare Settings: Recommendations of the Healthcare Infection Control Practice Advisory Committee and the HICPAC/SHEA/ APIC/IDSA Hygiene Task Force, 2002, 58 pp. 13 Canada Communicable Disease Report Supplement. Infection Control Guidelines: Hand washing, cleaning, disinfection and sterilization in health care. December 1998;24(S8). 14 Infection Control Nurses Association. Guidelines for Hand Hygiene, 2002. 15 Pratt RJ, Pellowe C, Loveday HP, Robinson N, Smith GW, and the guideline development team. The epic project: Developing national evidence based guidelines for preventing healthcare-associated infections. Phase 1: Guidelines for preventing hospital-acquired infec- tions. J Hosp Infect 2001;47(Supplement):S1–S82. 16 Ayliffe GA, Babb JR, Quoraishi AH. A test for ‘hygienic’ hand disinfection. J Clin Pathol 1978;31:923–928. 17 Ambulance Service Association. National Guidance and Procedures for Infection Prevention and Control. London: Ambulance Service Association, 2004. 18 Garner JS. The Hospital Infection Control Practices Advisory Committee: Guidelines for Isolation Precautions in Hospitals. Infect Control Hosp Epidemiol 1996;17(1):53–80. 19 Wilson J. Infection Control in Clinical Practice. London: Baillière Tindall, 1995:161–162. 20 Expert Advisory Group on AIDS and the Advisory Group on Hepatitis. Guidance for Clinical Health Care Workers: Protection Against Infection with Blood-Borne Viruses. London: Department of Health, 1998, 46 pp. 21 Centers for Disease Control Update. Recommendations for prevention of HIV transmission in health care settings. Morb Mort Week Rep 1987;37:24. 22 Garner JS. The Hospital Infection Control Practices Advisory Committee: Guidelines for Isolation Precautions in Hospitals. Infect Cont Hosp Epidemiol 1996;17(1): 53–80. 23 Pratt RJ, Pellowe C, Loveday HP, Robinson N, Smith GW, and the guideline development team. The epic project: Developing national evidence based guidelines for preventing healthcare-associated infections. Phase 1: Guidelines for preventing hospital-acquired infec- tions. J Hosp Infect 2001;47(Supplement):S1–S82. 24 Clark L, Smith W, Young L. Protective Clothing; Principles and Guidance. London: ICNA, 2002. 25 Callaghan I. Bacterial contamination of nurses’ uniforms: a study. Nurs Stand 2002;13(1):37– 42. 26 Perry C, Marshall R, Jones E. Bacterial contamination of uniforms. J Hosp Infect 2001;48:238– 241. 27 Huntley DE, Campbell J. Bacterial contamination of scrub jackets during dental hygiene procedures. J Dent Hyg 1998;72(3):19–23. 28 Health and Safety Commission. Control of Substances Hazardous to Health Regulations 1999. Approved Codes of Practice. London: HSE Books, 1999. 29 National Patient Safety Agency. The National Specifications for Cleanliness in The NHS: A Framework for Setting and Measuring Performance Outcomes in Ambulance Trusts. London: NPSA. 30 Department of Health. Standards for Better Health. London: Department of Health, 2006. 31 Department of Health. Ambulance Guidelines: Reducing Infection Through Effective Practice in the Pre-Hospital Environment. London: Department of Health, 2008. 238

Chapter 13 Vascular access devices Content Definition of a vascular access device 240 Anatomy of veins 240 Peripheral cannulas 241 Indications for peripheral cannulation 242 Selection of device for peripheral cannulation 242 Selection of vein 243 Techniques of venodilatation 244 Complications of peripheral venous cannulation 245 Procedure for peripheral intravenous cannulation 247 Intraosseous infusion 257 Anatomy of bones 257 Indications for intraosseous access 257 Contraindications to intraosseous access 258 Equipment for intraosseous access 258 Complications of intraosseous access 258 Location sites for intraosseous access 258 Procedures for intraosseous access 259 Chapter key points 266 References and Further reading 266 239

Chapter 13 Vascular access devices Vascular access and injections are tasks that are carried out quite commonly by ambulance paramedics. Intravenous cannulation is perhaps the most frequently used route of vascular access with the intraosseous route normally reserved for young children. The development of new devices may lead to an increase in the use of the intraosseous route in the emergency management of adults where intrave- nous access is unattainable. The skills are fundamental for the administration of many drugs and fluids but have inherent risks attached to them; the paramedic should be aware of the options available and select the most appropriate for the circumstances. Definition of a vascular access device For the purposes of prehospital care, a vascular access device is a device that is inserted into a peripheral or central vein (intravenous), or into the marrow cavity of selected bones (intraosseous). The devices may be used to administer drugs or fluids, or as a prophylactic measure. They may be used for sampling blood for diagnostic tests although this is not currently within the remit of UK paramedics. There is a variety of vascular access devices available and each has its own requirements; however, there are certain principles that are applicable to all devices. Anatomy of veins The superficial veins of the upper limbs are normally selected for siting a peripheral cannula in prehospital care. Use of the lower limbs may be indicated in very small children and where injury prevents the use of the upper limbs but cannu- lation of the lower limbs is associated with an increased risk of venous thromboem- bolism.1 Veins consist of three layers:2 • Tunica adventitia – the outer layer of fibrous connective tissue. • Tunica media – the middle layer comprising of smooth muscle and elastic fibres. • Tunica intima – the thin inner layer of endothelium. The skin consists of two layers:2 • Epidermis – the superficial thinner layer of the skin composed of keratinised stratified squamous epithelium. • Dermis – a layer of dense, irregular connective tissue lying deep to the epi- dermis. Blood vessels, nerves, glands and hair follicles are embedded in dermal tissue. The structure and appearance of the skin alters with age as the dermal layers become thinner and elasticity is lost. The number of cells producing collagen and elastic fibres decrease leading to the development of wrinkles. The veins of older people may be easier to see as a result of these changes but they are more mobile, more fragile, and often tortuous and thrombosed.3 It is perhaps best to avoid the dorsum of the hand in older people due to their fragile nature.5 240

Vascular access devices Chapter 13 Peripheral cannulas There are two commonly used peripheral cannulas; a peripheral cannula, and a hollow-needle infusion device, often called a ‘butterfly’ (see Figures 13.1 and 13.2). The peripheral cannula is usually a catheter-over-needle design; the needle is with- drawn after the venepuncture whilst the flexible plastic catheter remains in the vascular compartment. The needle of the butterfly remains in the vein thereby causing increased risk of damage to the vein.4 Peripheral cannulas are available to paramedics in various sizes ranging from 22 gauge (smallest) through to 14 gauge (largest). Each device is colour-coded and information regarding flow rates and catheter diameters can be found on the device packaging. Modern catheters tend to be made from polyurethane, which is more flexible, less traumatic and less irritating on the intimal layer of the vein than earlier polyvinyl chloride (PVC) models.5,6 Figure 13.1 Intravenous cannulas. 241

Chapter 13 Vascular access devices Figure 13.2 Butterfly cannula. Indications for peripheral cannulation Peripheral cannulas are indicated for: • Drug therapy • Fluid therapy • Prophylaxis. There are potential complications associated with intravenous cannulation so care should be taken to perform cannulation only on patients who are likely to benefit from the procedure. The risks associated with prophylactic cannulation probably outweigh the benefits so cannulation for this purpose is to be discouraged. Selection of device for peripheral cannulation The choice of cannula will be dependent upon several factors: • Purpose of cannulation. A larger bore cannula will be required for rapid infusion of fluids whilst a smaller gauge will be adequate for drugs or for prophylactic purposes. • Size of veins. Smaller veins will only tolerate a small cannula so irrespective of the purpose of cannulation, a small cannula may be required. • Shocked patients. Shock leads to peripheral shutdown and may restrict the size of cannula that can be inserted. • Practitioner skill and confidence. A newly qualified practitioner may be less confident at placing a large bore cannula so may take a pragmatic view that something is better than nothing. 242

Vascular access devices Chapter 13 Selection of vein An advantage of peripheral venous cannulation is that the veins are normally visible; however, there may be occasions where this is not the case so palpation and famil- iarity with venous topography are useful. Figures 13.3 and 13.4 illustrate venous anatomy in the hand and forearm. The vein should be selected before the device so that only an appropriate device is selected. The vein should be straight, free of valves and should feel ‘bouncy’ when palpated. It is best to avoid joints as there is increased risk of mechanical phlebitis and intermittent flow of fluids or drugs created by the patient’s movements. Vein selection will be dependent upon a number of factors including the reason for the cannulation, accessibility of the veins, injuries to the patient, and previous cannulation attempts. The initial attempt should be undertaken at the distal end of the limb as an unsuccessful attempt hinders the use of veins distal to the original site. A cannula should not be placed in areas of localised oedema, dermatitis, cel- lulitis, arteriovenous fistulae, wounds, skin grafts, fractures, stroke, planned limb surgery and previous cannulation.5 It may also be beneficial to patient independence if the cannula is placed in the non-dominant limb. Right cephalic Right dorsal venous network of the hand (dorsal venous arch) Right dorsal metacarpal Right dorsal digital Posterior view of superficial veins of the hand Figure 13.3 Veins of the hand. Reprinted from Jenkins, Kemnitz and Totora, Anatomy and Physiology; From Science to Life, copyright 2006, with permission of John Wiley & Sons Inc. 243

Chapter 13 Vascular access devices Right external jugular Right Right external Right Right subclavian internal jugular internal Right jugular jugular brachiocephalic Right subclavian Superior Right axillary vena cava Right basilic Right brachiocephalic Right cephalic Superior Right Right accessory vena cava axillary cephalic Right Sternum Right cephalic brachial Right median cubital Right basilic Right median Right Right ulnars antebrachial radials Right deep Right palmar palmar venous arch venous plexus Right superficial Right palmar palmar venous arch digital Right common palmar digital Right palmar Right proper metacarpal palmar digital Anterior view of superficial veins Anterior view of deep veins Figure 13.4 Veins of arm. Reprinted from Jenkins, Kemnitz and Totora, Anatomy and Physiology; From Science to Life, copyright 2006, with permission of John Wiley & Sons Inc. Techniques of venodilatation Tourniquet and Gravity Apply venous tourniquet to limb and tightened to between the patient’s systolic and diastolic pressures. If veins are not readily apparent or appear small in calibre, place the limb below the level of the heart.8 Gravity serves to slow venous return, leading to increased venous volume and distention of veins of the upper extremity.11 Fist clenching Opening and closing of the fist augments venous return by virtue of muscular com- pressive forces exerted on vessels to enhance arterial blood flow,7 which results in local venous distention.8 Increased blood velocity from fist clenching also increases venous flow to the basilic and cephalic veins.9 Research has shown that this form of isometric activity also results in vasodilatation.10 Vein ‘tap’ and ‘milking’ Tapping a superficial vein once or twice augments vein distention11 although the mechanism by which this occurs is unclear.8 Applying a mild, sliding pressure (‘milking’) along a short length of vein, from proximal to distal, displaces blood 244

Vascular access devices Chapter 13 distally resulting in vein distention.8 Care must be taken not to apply overly vigorous stimuli, especially to those with fragile superficial veins (e.g., elderly, those chroni- cally on steroids) so as not to injure the veins or to result in pain related reflex vasoconstriction.8 ‘Slapping’ the vein is painful and causes the release of histamine – this technique should not be used. Local warmth Blood flow in human skin increases greatly in response to direct heating 12 although care has to be taken not to induce thermal damage to the extremity. Applying local warmth in the prehospital environment may be difficult but consideration may be made to immersing the upper extremity in warm water for a few minutes, or apply- ing a warm, moist compress.13 Dilatation of the external jugular vein (EJV) The Valsalva manoeuvre (forced expiration through a closed glottis) for 30 sec (at a pressure of 40 mmHg) has been shown to result in an 86% increase in the area and 41% increase in the circumference of the right EJV.14 Similarly, use of the Tren- delenburg position augments venous return towards the right atrium and can result in EJV distention.15,16 Complications of peripheral venous cannulation No clinical intervention is risk free but the benefits of appropriate intravenous can- nulation are normally considered to outweigh the complications. One of the key concerns in prehospital care is the time delay for undertaking the task. Studies suggest that intravenous cannulation with no therapeutic treatment can increase on-scene times by an average of between 8 and 13 minutes,17,18 this needs to be considered when making the clinical decision to cannulate as should the number of attempts that should be made. Intravenous cannulation provides a direct portal of entry for infectious pathogens and is a considerable source of morbidity and mortality in hospital.19,20 The incidence of infection secondary to intravenous cannulation by paramedics is not known but the nature of the work and the practice environment mean that it could be even higher. An increased risk of infection during emergency insertion has been noted as strict adherence to aseptic techniques may be less rigorous.21 Places, people and equipment can all serve as reservoirs for infection.22 For this reason infection pre- vention and control should consider not only patients, but also staff and bystanders as well as the environment and any equipment in use.23 Whilst the paramedic may have limited control over the environment, they can minimise the risk of infection from equipment by ensuring that any packaging is intact and in date. When opening packaging, aseptic techniques should be employed. Compliance with hand hygiene and personal protective equipment policies is imperative in order to minimise the risks of contamination through this portal and, although there is debate regarding the efficacy of skin cleansing prior to insertion, current recommendations advocate the use of 2% chlorhexidine gluconate in 70% isopropyl alcohol, which should be allowed to dry.24 245

Chapter 13 Vascular access devices The incidence of vascular complications increases as the ratio of the external diameter of the cannula to vessel lumen increases;25 therefore the smallest cannula for the prescribed therapy should be used.5,26,27 Phlebitis related to intravenous can- nulation has three underlying factors; mechanical (caused by friction and movement of the device within the vein), chemical (relating to infusates), and physical (related to the properties of the cannula).28 Identify common sources of contamination during intravenous cannulation and describe how to minimise these risks. Other potential complications and their solutions are presented in Table 13.1. Management in situ Once sited, the peripheral cannula should be flushed with 0.9% sodium chloride or a heparin solution. The exact volume of fluid required to maintain patency is unclear but between 2 and 5 mL is adequate providing correct technique is used; i.e. a pul- satile flush ending with positive pressure.25 Once the cannula is in situ it should be taped into place for security. Non-sterile tape should not cover the site; it should be treated as an open wound. Specific cannula dressings are supplied and should be used as they are sterile and allow vision of the site during fluid/medication administration. 246

Vascular access devices Chapter 13 Table 13.1 Insertion and devices: complications and solutions Risks with Impact Management insertion of devices Delay in treatment and unable to use Review technique, vein and vein equipment selection. Attempt again Failed technique only if necessary and chances of success are high Poor technique Pain, nerve hit, overshot vein, bruising, Patient anxiety increased risk of infection, patient Refer to more experienced anxiety, failed attempt colleague; work to improve technique under supervision Vein may be constricted, muscles may be tense so risk of pain Reassure patient, select smallest suitable device, consider local Incorrect device Device performs poorly, flow rate anaesthetic, consider necessity Sharps disposal inadequate or fluid overload, causes of procedure in prehospital mechanical phlebitis environment Needlestick injury for staff or patient Remove device and perform full assessment Plastic/air embolus Risk of pulmonary embolism Wash wound in running water and Patient compliance Device removed or tampered with follow local policy Haematoma Bruising, pain, reduced access to vein Remove device and treat any symptoms, report on arrival at Occluded cannula Fails to allow fluid or medication hospital and document incident delivery Assess patient, ensure appropriate site selection and secure device Remove device and apply pressure Remove device and re-site Adapted from Lavery and Smith 2007.6 Procedure for peripheral intravenous cannulation Equipment required • Gloves • Selection of peripheral venous cannulas (select smallest for the intended purpose) • Venous tourniquet • 2% chlorhexidine gluconate in 70% isopropyl alcohol • Sterile occlusive transparent semi-permeable membrane (e.g. Vecafix, Niko- Gard) • Intravenous administration set or 0.9% sodium chloride flush • Sharps box. 247

Chapter 13 Vascular access devices Procedure (Figures 13.5–13.13) Additional information/rationale Preparation 1. Explain the procedure and gain consent. Legal requirement. 2. Select site for cannula placement. Straight, wide veins; ‘bouncy’ on palpation; avoid joints and valves. 3. Prepare equipment. Check date and integrity of package. Check all component parts are present. Technique 1. Use a non-touch insertion technique29 Minimises risk of infection. 2. Apply tourniquet. To engorge veins the tourniquet should be tightened to between the patient’s systolic and diastolic pressures. 3. Perform hand hygiene and, wearing gloves, Minimises the risk of infection. disinfect the selected venepuncture site, allowing at least 30 seconds for the site to dry.27 4. Inspect the chosen cannula to ensure product Ensure the package is intact and the integrity. To avoid contamination do not touch the expiry date has not been exceeded. cannula shaft. 5. Hold the cannula in line with the vein at a 10–30 ° angle to the skin and insert the cannula through the skin. 6. As the cannula enters the vein, blood will be Return of blood into the cannula is seen in the flashback chamber. required to confirm correct placement of cannula in the vein.30 7. Lower the angle of the cannula slightly to The needle sits ahead of the catheter ensure it enters the lumen of the vein and does so the cannula may need to be not puncture the posterior wall of the vessel; advanced a little further to ensure that advance the needle a little further. the catheter is in the vein. 8. Withdraw the stylet slightly and blood should be Confirms the position in the vein. seen to enter the cannula. Slowly advance the cannula into the vein, ensuring that the vein remains anchored throughout the procedure. NB: The stylet must not be re-inserted as this can damage the cannula, resulting in plastic embolus. 248

Vascular access devices Chapter 13 Procedure (Figures 13.5–13.13) Additional information/rationale 9. Release the tourniquet Allows free flow of fluids/drugs and relieves pressure from patient’s arm. Prevents flow of blood out of the distal end of the cannula as the needle is removed. 10. Place pressure distal to the end of the catheter Drop sharps into container; do not and remove needle; immediately place needle into push. Colleagues should NOT hold the sharps bin then replace bung onto the end of the sharps container so as to avoid risk of cannula or connect giving set. accidental needlestick injury. 11. Connect cannula to pre-prepared infusion giving Confirms patency and ensures easy set or flush with 0.9% sodium chloride (or heparin administration without pain, resistance solution). or localised swelling. 12. Apply a sterile dressing. 13. Secure administration set tubing if an infusion is started. 14. Remove gloves and perform hand hygiene. Post-procedure 1. Note the date and time of insertion on the case It is recommended that cannulas report form. Some cannula dressings may also inserted in emergency conditions are have facility for documenting this information. replaced within 24 hours of inser- tion21,32 2. Document the number of attempts and any Allows hospital staff to monitor any other complications. untoward occurrences. 3. Splints should only be used when the cannula is If a splint is used, removal to allow placed in an area of flexion or is at risk of assessment of the circulatory status of dislodgment.31 the limb is required at established intervals.31 249

Chapter 13 Vascular access devices Figure 13.5 Disinfect chosen site. Figure 13.6 Insert needle at angle of between 10 and 30 degrees. 250

Vascular access devices Chapter 13 Figure 13.7 Blood in flashback chamber. Figure 13.8 Blood enters the catheter as the needle is withdrawn. 251

Chapter 13 Vascular access devices Figure 13.9 Advance cannula whilst anchoring the vein. Figure 13.10 Remove needle whilst applying distal pressure 252

Vascular access devices Chapter 13 Figure 13.11 Safe disposal of sharps. Figure 13.12 Replace bung onto the end of the cannula. 253

Chapter 13 Vascular access devices Figure 13.13 Secure cannula and document time. Hollow needle device (butterfly) These devices are suited for use on children or other patients with small, delicate veins. They do not have a polyurethane catheter; rather, the metal stylet is inserted into the vein and secured there. There is a risk of damage to the vein with the metal needle so care is needed when inserting and securing the device. A similar technique to standard peripheral cannulation is used except that there will be no flashback of blood and the needle remains in situ. External jugular cannulation The external jugular vein (EJV) crosses the sternomastoid muscle and then tra- verses the posterior triangle of the neck superficially. It is easily distended by a simple Valsalva manoeuvre. The EJV is superficial when it crosses the posterior triangle so it is safe for venepuncture. No important structures lie so superficially in the neck and therefore inadvertent muscle, arterial or nerve injury is avoided.33 The close proximity of the external jugular vein to the central venous system offers many of the benefits conferred by central venous cannulation; fluids and medications rapidly reach the core of the body from the EJV. Access to the EJV should only be considered where other means of peripheral access have been exhausted, so it will most likely be reserved for the cardiac arrest situation. Cannulation of the EJV requires largely the same equipment as for cannulation at other peripheral sites although a 10 mL syringe is also required to aspirate blood to help confirm entry; a venous tourniquet is not required. 254

Vascular access devices Chapter 13 Complications There are several complications in addition to those of other sites of peripheral intravenous cannulation: • Puncture of the airway • Damage to nearby arterial vessels • The technique should not be used in suspected cervical spine injury • Only one attempt may be used in prehospital care. Procedure for external jugular cannulation Procedure Additional information/rationale Preparation 1. Explain the procedure and gain consent (where applicable). 2. Prepare equipment. Check date and integrity of package. Check all component parts are present. Draw 3–5 mL of saline into the 10 mL syringe and connect the syringe to the flashback chamber of a large-bore catheter over needle cannula. 3. Position the patient supine with feet elevated or Increases blood flow to the chest and use Trendelenburg position. neck and decreases the chance of air entering the circulatory system during cannulation.34 4. Turn the patient’s head in the direction away Helps to expose the vein to be from the site to be cannulated. cannulated. Technique 1. Perform hand hygiene and, wearing gloves, Minimises the risk of infection. disinfect the selected venepuncture site, allowing at least 30 seconds for the site to dry.27 Start swabbing at the site of intended puncture and work outward 2.5–5 cm in increasing circles. 2. Engorge vein: Occlude venous return by placing Engorges vein prior to cannulation. a finger on the EJV just above the clavicle; this Never apply a tourniquet around the also anchors the vein. patient’s neck. 255

Chapter 13 Vascular access devices Procedure Additional information/rationale 3. Point the cannula at the medial third of the clavicle and insert it at an angle of between 10 o and 30 o. The bevel of the needle should be up. 4. As the cannula enters the vein, gently ease back Return of blood into the syringe is on the plunger; if blood enters the syringe, required to confirm correct placement proceed with insertion. Advance the entire cannula of cannula in the vein.35 a further 0.5 cm so that the catheter has entered the vein; slide the catheter into the vein and remove the needle as previously described. 5. Dispose of needle safely. Drop sharps into container do not push. Colleagues should NOT hold the sharps container so as to avoid risk of accidental needlestick injury. 6. Connect cannula to pre-prepared infusion giving Ensures correct insertion. set and allow to run free for several seconds. 7. Once position confirmed, set flow to appropriate rate. 8. Apply a sterile dressing. 9. Secure administration set tubing if an infusion is started. 10. Remove gloves and perform hand hygiene. Post-procedure 1. Note the date and time of insertion on the case It is recommended that cannulas report form. inserted in emergency conditions are replaced within 24 hours of inser- tion.21,36 2. Document the number of attempts and any Legal requirement and allows hospital other complications on case report form. Some staff to monitor any untoward cannula dressings may also have facility for occurrences. documenting this information. 256

Vascular access devices Chapter 13 Intraosseous infusion Intraosseous infusion (IOI) is an excellent alternative route for providing vascular access to administer fluids, blood products, and medications where alternative methods are not available or attempts have failed. IOI is particularly useful in chil- dren and studies have demonstrated that the use of IOI can decrease the time needed to obtain vascular access in paediatric patients in cardiac arrest.37,38 In addition, the rate of vascular access in paediatric cardiac arrest patients is higher for IOI (83%) than for all other forms of IV access,39 and a recent study sug- gests that the IO route provides vascular access and fluid more quickly under HazMat conditions.40 IO has been widely used in the United States for a number of years41 and there is evidence that IO devices can be easily placed compared with intravenous access by combat medics.42 Anatomy of bones Bone is made up of a dense outer layer surrounding a spongy inner layer that forms a meshwork occupied by bone marrow, blood vessels, nerves, and fat tissue.43 Bone marrow consists of developing blood cells and a network of fibres that support the vascular complex in the medulla. The purposes of the medullary complex include production of red blood cells and provision of a blood supply to the bone itself. The medullary cavity of long bones provides a ‘non-collapsible vein’ for intraosseous access. Indications for intraosseous access The basic indication for IOI is the need for emergent vascular access when conven- tional methods have failed.44 The Resuscitation Council state that the IO route should be considered for both adults and children where intravenous access is difficult or impossible.45 IOI has also been recommended for conditions such as cardiopulmo- nary arrest, profound shock, status epilepticus, overwhelming sepsis, and major burns.46,47 You are about to administer an IOI to a young child – consider how you will gain consent from the parents and how you will reassure them during the procedure 257

Chapter 13 Vascular access devices Contraindications to intraosseous access The only universally accepted absolute contraindication to IOI is a fracture of the bone near the access site.48 Relative contraindications to IOI include cellulitis over the insertion site and inferior vena caval injury.48 Equipment for intraosseous access Several devices are now available for use although most ambulance Trusts in the UK retain the traditional ‘Cook’ style device. The EZ-IO (a drill device), the Bone Injection Gun (BIG) (an automatic intraosseous device) and the FAST IO intro- ducer are available and have met with varying reviews. The new devices will be discussed along with the traditional device in order to cover all of those used in UK practice. Complications of intraosseous access Very few complications have been reported in association with IO access.49 In more than 4200 cases of IO access in children, osteomyelitis occurred in only 0.6%, and usually only if the infusion continued for a prolonged period or if the patient had bacteraemia at the time of insertion.50 In a prospective, 250-patient, multi-centre study of the powered drill device, no observed cases of osteomyelitis, fat embolism, fracture, infection, extravasation, or compartment syndrome were found.51 Pain during insertion and infusion under pressure are likely to be of concern. One study showed average pain ratings of 5 on a 1–10 severity scale during IO infusion in conscious patients.51 A separate study using the drill device in 125 conscious patients, recorded an average pain score of 1.2 on a five-point scale, 1 being lowest and 5 being greatest.52 The use of 1% lidocaine injected into the marrow space over 60 seconds has been shown to be effective in reducing pain during infusion.53 Location sites for intraosseous access The conventional site for IOI is the proximal tibia.54 The tibial tuberosity can be located by palpation just below the patella. The usual insertion site is the relatively flat area 2 cm distal and 2 cm medial to the tibial tuberosity. Although this site is usually distal to the growth plate, it is still recommended that the needle be angled 10–15 degrees caudally to avoid injury to the growth plate.44 There are several alternative sites including the distal tibia in children. To avoid the saphenous vein, the distal tibia may be entered 1–2 cm superior to the medial malleolus. It is recommended that the needle be angled (10–15 degrees) away from the growth plate (i.e., cephalad in this instance).44 The sternum carries a number of problems: it may interfere with chest compres- sions and carries a risk of mediastinal injury, pneumothorax, great vessel injury, and death.55 However, new devices such as the FAST have improved the safety of sternal access, and may now provide an option for prehospital providers. 258

Vascular access devices Chapter 13 Procedures for intraosseous access Traditional IO device Procedure Additional information/rationale 1. Explain the procedure and gain consent of Legal requirement. patient or relative. 2. Restrain the patient’s leg and place Brings leg into best position for insertion padding under the knee. and prevents accidental misplacement if patient moves during insertion. 3. Identify the chosen site – usually the tibia. The landmark on the tibia for all age groups can be found by: • Identifying the tibial tuberosity. • Find a point 2 cm inferior to the tibial tuberosity and then 2 cm medial to that point. 4. Clean the skin. There is no set method for doing this but the risk of infection and the problems associated with managing bone infections suggest that a rigorous technique be used. 5. If approved for use, administer local Reduces pain during procedure. anaesthetic to the conscious patient (1% lidocaine injected subcutaneously and over the periosteum). 6. Insert IO needle through the skin and Indicates entry into the marrow. subcutaneous tissues until bone is felt. Using a twisting motion, insert the trocar into the bone until a loss of resistance or ‘pop’ is felt, do not insert any further. 7. Remove the trocar from the needle dispose Health and safety of sharps. of safely. 8. Attach a saline filled syringe; pull back on Confirms correct placement. the plunger to attempt aspiration into the syringe. 9. If marrow is not aspirated, push a 5 to Correct medullary placement can be 10 mL bolus of isotonic sodium chloride confirmed when bone marrow and blood solution through the syringe. can be easily aspirated. 259

Chapter 13 Vascular access devices Procedure Additional information/rationale 10. If flow is good and extravasation is not Resistance to flow should be minimal, and evident, connect an intravenous line with a extravasation should not be evident. 3-way stopcock, and secure the needle with Observing the calf area for acute swelling gauze pads and tape. or discoloration is important. 11. Fluids may infuse by gravity but the Flow rates can be dramatically increased by unpredictability of bone marrow blood flow by the use of pressure bags and infusion this method alone has been demonstrated 56 pumps. Flow rates of 10 mL/min by gravity so it is usually necessary to use pressure to can be increased to 41 mL/min by using augment flow in IOI. pressurized bags.58 An alternative method for rapid infusion is to manually infuse 30–60 mL boluses via a stopcock. 12. Only one IO attempt should be made in Multiple punctures in the periosteum may each bone. However, if the needle becomes result in extravasation of fluid into the soft plugged with soft tissue, it may be removed, tissues. and a new needle may be inserted through the same cannulation site.57 13. Complete documentation. Virtually all drugs that can be administered via the IV route can be administered by IOI.59 There is no need to adjust drug dosages when using the IO route because it has been demonstrated that different IOI sites (humerus, femur, malleolar, and tibia) are pharmacokinetically equivalent with regard to transit times and serum concen- trations.60 EZ-IO The EZ-IO® Intraosseous Infusion system is a system that allows for immediate vascular access in all patients larger than 3 kg. It comprises of a power driver that 260 provides a minimum of 1000 insertions and has a shelf life of up to 10 years, and needle sets of varying sizes to match the needs of the patient. There is little research available at the moment, but the small scale studies that have been completed suggest that it is a useful tool. One study has shown that vascular access using the EZ-IO is achieved significantly more frequently at first attempt than a manual IO system (Cook),61 whilst there has also been successful use by the military.62 However, pain has been observed in conscious patients and in one study, insertion of the EZ-IO proved to be more painful than the original injury.63 A small study investigated the use of the EZ-IO for humeral and tibial insertion and found that both sites had high- insertion success rates and there was no significant difference in tibial or humeral flow rates.63 This may open up an alternative site for when tibial insertion is not an option.

Vascular access devices Chapter 13 Procedure EZ-IO64 See Figure 13.14. • Follow first 5 steps above. • Prepare infusion system. • Ensure that the driver and needle set are securely seated. • Remove and discard the needle set safety cap from the IO needle set installed on the EZ-IO power driver. • Position driver at insertion site with needle set at a 90-degree angle to the bone. Gently power or press needle set until needle set tip touches bone. • Ensure at least 5 mm of the catheter is visible. • Penetrate bone cortex by squeezing the driver’s trigger and applying gentle, steady downward pressure. • Release driver’s trigger and stop insertion process when: • A sudden ‘give’ or ‘pop’ is felt upon entry into the medullary space. • A desired depth is obtained. • Remove power driver and stylet. • Confirm catheter stability. • Attach primed EZ-Connect® extension set to catheter hub’s Luer lock and confirm position; proceed as before. Figure 13.14 EZ-IO. Reproduced with permission of Vidacare (UK) Ltd. 261

Chapter 13 Vascular access devices FAST The FAST™ is a sternal intraosseous infusion device that delivers life-saving drugs and fluids to the heart in under a minute. It is specifically designed for safe and effective use of IO under emergency conditions and features speedy access, a pro- tected infusion site, and a depth-control mechanism. The tool allows IO infusion to be used as a standard protocol in adults. The FAST is only designed to be used in patients aged 12 years or older and is intended to be inserted only in the midline of the manubrium 1.5 cm inferior to the suprasternal notch. A second generation device, the ‘FAST X’, is being developed but was not available at time of writing; the infor- mation given here relates specifically to the FAST 1 (Figure 13.15). Studies suggest that the FAST has considerable potential in prehospital care65–67 although more work is probably required. Figure 13.15 FAST 1. Reproduced with permission of Pyng Medical Corporation. 262

Vascular access devices Chapter 13 Procedure for FAST Procedure Additional information/rationale 1. Explain the procedure and gain consent of patient Legal requirement. or relative. 2. Expose the sternum and clean the infusion site. There is no set method for cleaning Clean the skin. the site but the risk of infection and the problems associated with managing bone infections suggest that a rigorous technique be used. 3. Remove top half of patch backing (labelled ‘Remove This point is needed to correctly 1’). Locate sternal notch with index finger held perpen- place the ‘target zone’ of the patch. dicular to manubrium. 4. Using index finger, align notch in patch with the Ensures that the correct point on patient’s sternal notch ensuring that the target zone the manubrium will be entered by (circular hole in Patch) is over the patient’s midline. the device. 5. Remove the bottom half of the Patch backing (labelled ‘Remove 2’) and press Patch firmly to secure it to the patient. 6. Verify that the target zone is over the patient’s Errors of greater than 1 cm may midline; adjust the Patch if the error is greater than cause misplacement of the device about 1 cm. and may cause injury. 7. Remove the sharps cap from the introducer. 8. Place bone probe cluster (series of needles) in the The introducer must remain target zone ensuring that the introducer axis is perpendicular in order that the perpendicular (90 °) to the skin at the insertion site. insertion tube is correctly sited. Ensure that the entire bone probe cluster is within the target zone. 9. Pressing straight along the introducer axis, with hand and elbow in line, push with firm increasing pressure until a distinct release is heard and felt. The introducer must remain perpendicular to the skin during insertion. 10. After release, pull straight back on the introducer to expose the infusion tube. 11. Push the used bone probe cluster into the Enables safe disposal of sharps. foam-filled sharps plug. Replace the original sharps cap over the sharps cover if desired. 12. Attach the elbow female connector (blue cap) on the patch to the infusion tube male Luer. 263

Chapter 13 Vascular access devices Procedure Additional information/rationale 13. Attach a syringe with 2–3 mL of sodium chloride to Required to create a clear passage- the infusion tube and push through quickly – NOTE: way for fluid administration. this will be very painful if the patient is conscious. 14. Attach the straight female connector on the patch to the IV set. 15. If fluid does not flow or extravasation occurs, the infusion should be discontinued and an alternative vascular access method should be used. 16. Complete documentation. Bone injection gun (BIG) See Figure 13.16. The bone injection gun was perhaps the first automatic IO device and was intro- duced into emergency medicine in 2000. There have been mixed reviews when compared with standard IO techniques or alternative powered/automatic devices. A Best Evidence Topic report from 200568 concluded that the bone injection gun appears to be equivalent in terms of success and possibly (but not clinically signifi- cantly) faster to use than standard IO needles at achieving IO access, whilst a pro- spective study suggested that the bone injection gun provides an effective alternative IV access for critical patients in whom a peripheral IV line cannot be Figure 13.16 Bone injection gun. 264

Vascular access devices Chapter 13 readily obtained in the prehospital setting.69 There have also been case reports of high failure rates when using the BIG device caused mainly by the inability to control the path of the catheter.70 As with other recent automatic IO devices it is likely that more work needs to be done with the B.I.G before its effectiveness can be fully established. Procedure for bone injection gun Procedure Additional information/rationale 1. Explain the procedure and gain consent of Legal requirement. patient or relative. 2. Locate a suitable penetration site. Primary site in adults is the proximal tibia, secondary sites include the medial malleolus, distal radius and anterior head of the humerus. 3. Clean the infusion site. There is no set method for cleaning the site but the risk of infection and the problems associated with managing bone infections suggest that a rigorous technique be used. 4. Choose BIG with desired depth of penetration. 5. With one hand holding firmly, position the BIG Ensures that the correct point will be at a 90 degree angle to the surface of the skin. entered by the device. 6. With one hand holding the BIG firmly, pull out Do not dispose of safety latch, it will be the safety latch by squeezing its two sides used later. together. 7. While continuing to hold the bottom part No extra force is required. firmly against the leg, place 2 fingers of the other hand under the ‘winged portion’ and the palm of that hand on the top. Leaning on the device with straight elbows will activate the BIG. 8. Trigger the BIG by gently pressing down. 9. Pull out the stylet trocar to leave the cannula in the bone. 10. The safety latch can now be used to provide Helps to prevent instability in the cannula extra stability to the cannula. and reduces the risk of displacement. 11. Proceed as for conventional IOI. 265

Chapter 13 Vascular access devices Chapter Key Points 1. A vascular access device is a device that is inserted into a peripheral or central vein (intravenous), or into the marrow cavity of selected bones (intraosseous). 2. The structure and appearance of the skin alters with age as the dermal layers become thinner and elasticity is lost. The veins of older people may be easier to see as a result of these changes but they are more mobile, more fragile, and often tortuous and thrombosed. 3. There are two commonly used peripheral cannulas; a peripheral cannula, and a hollow-needle infusion device, often called a ‘butterfly’. 4. The choice of cannula will be dependent upon several factors such as the purpose of cannulation, the size of veins, peripheral shutdown in shocked patients, and the practitioner’s skill and confidence. 5. Appropriate techniques should be used to encourage venodilatation. 6. The benefits of appropriate venous cannulation normally outweigh the risks but the practitioner needs to be aware of the risks and minimise any dangers. 7. Intraosseous infusion is an excellent alternative route for providing vascular access to administer fluids, blood products, and medications where alternative methods are not available or attempts have failed. 8. New devices for obtaining intraosseous access mean that this route may become more widely used in the future. 9. The only universally accepted absolute contraindication to intraosseous infusion is a fracture of the bone near the access site. 10. Virtually all drugs that can be administered via the IV route can be administered by intraosseous infusion. There is no need to adjust drug dosages when using the IO route. References and Further reading 1 Scales K. Vascular access in the acute care setting, in Dougherty L, Lamb J (Eds) Intrave- nous Therapy in Nursing Practice. London: Churchill Livingstone, 1999, pp. 261–299. 2 Tortora GJ, Derrikson B. Principles of Anatomy and Physiology, 11th edn. New Jersey: Wiley, 2006. 3 Dougherty L. Obtaining peripheral venous access. In: Dougherty L, Lamb J. (Eds) Intrave- nous Therapy in Nursing Practice. London: Churchill Livingstone, 1999. 4 Dougherty L. Obtaining peripheral venous access. In: Dougherty L, Lamb J. (Eds) Intrave- nous Therapy in Nursing Practice. London: Harcourt, 1999. 5 Scales K. Vascular access: a guide to peripheral venous cannulation. Nurs Stand 2005;19(49):48–52. 6 Lavery I, Smith E. Peripheral vascular access devices: risk prevention and management. Br J Nurs 2007;16(22):1378–1383. 7 Campbell J. Making sense of the technique of venepuncture. Nurs Times 1995;91:29–31. 8 Mbamalu D, Banerjee A. Methods of obtaining peripheral venous access in difficult situa- tions. Postgrad Med J 1999;75:459–462. 9 Simons P, Coleridge Smith P, Lees WR, McGrouther DA. Venous pumps of the hand. Their clinical importance. J Hand Surg [Br] 1996;21:595–599. 266

Vascular access devices Chapter 13 10 Torok T, Bari F, Kardos A, Paprika D, Rudas L. Isometric handgrip exercise-induced musca- rinic vasodilation in the human skin microvasculature. Acta Physiol Hung 1997–98;85:193– 198. 11 Millam DA. Tips for improving your venipuncture techniques. Nursing 1987;17:46–49. 12 Savage MV, Brengelmann GL. Reproducibility of the vascular response to heating in human skin. J Appl Physiol 1994;76:1759–1763. 13 Lenhardt R, Seybold T, Kimberger O, Stoiser B, Sessler DI. Local warming and insertion of peripheral venous cannulas: single blinded prospective randomized controlled trial and single blinded randomised crossover trial. BMJ 2002;325:409–410. 14 Attubato MJ, Katz ES, Feit F, Bernstein N, Schwartzman D, Kronzon I. Venous changes occurring during the Valsalva maneuver: evaluation by intravascular ultrasound. Am J Cardiol 1994;74:408–410. 15 Verghese ST, Nath A, Zenger D, Patel RI, Kaplan RF, Patel KM. The effects of the simulated Valsalva maneuver, liver compression, and/or Trendelenberg position on the cross-sec- tional area of the internal jugular vein in infants and young children. Anesth Analg 2002;94:250–254. 16 Lobato EB, Florete OG Jr, Paige GB, Morey TE. Cross-sectional area and intravascular pres- sure of the right internal jugular vein during anesthesia: effects of Trendelenburg position, positive intrathoracic pressure, and hepatic compression. J Clin Anesth 1998;10:1–5. 17 Sukumaran S, Henry JM, Beard D, Lawrenson R, Gordon MWG, O’Donnell JJ, Gray AJ. Pre- hospital trauma management: a national study of paramedic activities Emerg Med J 2005;22:60–63. 18 Johnson GS, Guly H. The effect of pre-hospital administration of intravenous nalbuphine on on-scene times. Emerg Med J 12(1):20–22. 19 Parker I. Management of intravascular devices to prevent infection. Br J Nurs 11(4):240–246. 20 Pinkowish M. Bloodstream infections and intravascular devices. Am J Nurs 106(12):72CC– 72DD. 21 Tagalakis V, Kahn SR, Libman M, Blostein M. The epidemiology of peripheral vein infusion thrombophlebitis: a critical review. Am J Med 2002;113(2):146–151. 22 Chalmers C, Straub M. Standard principles for preventing and controlling infection. Nurs Stand 2006;20(23):57–65. 23 Damani NN. Manual of Infection Control Procedures, 2nd edn. London: Greenwich Medical Media, 2003. 24 Department of Health. High Impact Intervention No 2. Peripheral intravenous cannula care bundle. 2007 available online at www.clean-safe-care.nhs.uk [accessed 24–04–2008]. 25 Mallet J, Dougherty L. Manual of Clinical Nursing Procedures, 5th edn. Oxford: Blackwell Science, 2000. 26 Fuller A, Winn C. Selecting equipment for peripheral intravenous cannulation. Profess Nurse 1999;14(4):233–236. 27 Royal College of Nursing. Infusion equipment. In: Standards for Infusion Therapy, 2nd edn. London: RCN; 2006, pp. 18–24. 28 Workman B. Peripheral intravenous therapy management. Nurs Stand 14(4):53–60. 29 Centre for Disease Control. Guidelines for the Prevention of Intravascular Catheter-Related Infections. Morb Mort Week Rep 2002;51(RR10). 30 Royal College of Nursing. Site selection and placement. In: Standards for Infusion Therapy, 2nd edn. London: RCN, 2005, pp. 25–32. 31 Royal College of Nursing. Infusion equipment. In: Standards for Infusion Therapy, 2nd edn. London: RCN, 2006, pp. 18–24. 32 NHS Lothian University Hospitals Division. Venepuncture and/or Peripheral IV Cannulation Clinical Skills Education Pack. Edinburgh: NHS LUHD, 2005. 33 Mason S, Watts A, Shiels S, Koorey D. Improving access to HCV treatment: external jugular venepuncture can overcome problems with difficult venous access. Internat J Drug Policy 2007;18(5):433–436. 267

Chapter 13 Vascular access devices 34 Bledsoe B, Porter RS, Cherry RA. Essentials of Paramedic Care. New Jersey: Prentice Hall, 2003. 35 Royal College of Nursing. Site selection and placement. In: Standards for Infusion Therapy, 2nd edn. London: RCN, 2005, pp. 25–32. 36 NHS Lothian University Hospitals Division. Venepuncture and/or Peripheral IV Cannulation Clinical Skills Education Pack. Edinburgh: NHS LUHD, 2005. 37 Glaeser PW, Losek JD, Nelson DB et al. Pediatric intraosseous infusions: impact on vascular access time. Am J Emerg Med 1988;6:330–332. 38 Kanter RK, Zimmerman JJ, Strauss RH, Stoeckel KA. Pediatric emergency intravenous access: evaluation of a protocol. Am J Dis Child 1986;140:132–134. 39 Brunette DD, Fischer R. Intravenous access in pediatric cardiac arrest. Am J Emerg Med 1988;6:577–579. 40 Suyama J, Knutsen CC, Northington WE, Hahn M, Hostler D. IO versus IV access while wearing personal protective equipment in a HazMat scenario. Prehosp Emerg Care 2007;11:467–472. 41 Miner WF, Corneli HM, Bolte RG, Lehnhof D, Clawson JJ. Prehospital use of intraosseous infusion by paramedics. Pediatr Emerg Care 1989;5(1):5–7. 42 Calkins MD, Fitzgerald G, Bentley TB, Burris D. Intraosseous infusion devices: a comparison for potential use in special operations. J Trauma 2000;48(6):1068–1074. 43 Ross MH, Romrell LJ, Kaye GI. Histology: A Text and Atlas, 3rd edn. Baltimore, MD: Williams & Wilkins, 1995, pp. 150–153. 44 LaRocco BG, Wang HE. Intraosseous Infusion. Prehosp Emerg Care 2003;7:280–285. 45 Resuscitation Council UK. Adult advanced life support. 2005 available online at http://www. resus.org.uk/pages/als.pdf [accessed 04–05–2008]. 46 Hurren JS, Dunn KW. Intraosseous infusion for burn resuscitation. Burns 1995;21:285–287. 47 Goldstein B, Doody D, Briggs S. Emergency intraosseous infusion in severely burned chil- dren. Pediatr Emerg Care. 1990;6:1995–1997. 48 Miner WF, Corneli HM, Bolte RG, Lehnhof D, Clawson JJ. Prehospital use of intraosseous infusion by paramedics. Pediatr Emerg Care 1989;5(1):5–7 . 49 Fowler R, Gallagher JV, Isaacs SM, Ossman E, Pepe P, Wayne M. The role of intraosseous vascular access in the out-of-hospital environment (resource document to NAEMSP position statement). Prehosp Emerg Care 2007;11:63–66. 50 Rosetti VA, Thompson BM, Miller J, Mateer JR, Aprahamian C. Intraosseous infusion: an alternative route of pediatric intravascular access. Ann Emerg Med 1985;14(9):885–888. 51 Davidoff J, Fowler R, Gordon D, Klein G, Kovar J et al. Clinical evaluation of a novel intraos- seous device for adults: prospective, 250-patient, multi-center trial. JEMS 2005;30(10) (suppl):20–23. 52 Gillum L, Kovar J. Powered intraosseous access in the out-of-hospital setting. JEMS 2005;30(10)(suppl):24–26. 53 Waisman M, Waisman D. Bone marrow infusion in adults. J Trauma 1997;(2):288–293. 54 American College of Surgeons (Eds) ATLS, Advanced Trauma Life Support for Doctors, Student Manual. Chicago IL: American College of Surgeons, 1997, pp. 12, 97. 55 Fiser DH. Intraosseous infusion. N Engl J Med 1990;322:1579–1581. 56 Voelckel WG, Lurie KG, McKnite S et al. Comparison of epinephrine with vasopressin on bone marrow blood flow in an animal model of hypovolemic shock and subsequent cardiac arrest. Crit Care Med 2001;29:1587–1592. 57 Neal CJ, McKinley DF. Intraosseous infusion in pediatric patients. J Am Osteopath Assoc 1994;94(1):63–66. 58 Shoor PM, Berryhill RE, Benumof JL. Intraosseous infusion: pressure–flow relationships and pharmacokinetics. J Trauma 1979;19:772–774 . 59 Hazinski MF, Cummins RO, Field JM. (Eds) Basic life support for health care providers. In: Handbook of Emergency Cardiovascular Care for Healthcare Providers. Dallas TX: American Heart Association, 2002, pp. 1–2, 96. 268

Vascular access devices Chapter 13 60 Warren DW, Kissoon N, Mattar A, Morrissey G, Gravelle D, Rieder MJ. Pharmacokinetics from multiple intraosseous and peripheral intravenous site injections in normovolemic and hypo- volemic pigs. Crit Care Med 1994;22:838–843. 61 Brennera T, Bernharda M, Helmb M, Doll S, Völkl A, Ganiona N, Friedmanna C, Sikingera M, Knappa J, Martina E, Gries A. Comparison of two intraosseous infusion systems for adult emergency medical use. Resuscitation 2008;78:314–319. 62 Cooper BR. Intra-osseous access EZ-IO for resuscitation: UK military combat experience. J Royal Army Med Corps 2007;153(4):314–316. 63 Ong ME, Chan YH, Oh JJ, Su-Yin Ngo N. An observational, prospective study comparing tibial and humeral intraosseous access using the EZ-IO. Am J Emerg Med 2009;27(1):8–15. 64 Vidacare. EZ-IO intraosseous infusion system directions for use. 2006 available online at http://www.vidacare.com/reports/VDAA168EZ–IODFU051707.pdf [accessed 06–05–2008]. 65 Tiffany BR, Horwood BT, Pollack CV et al. Sternal intraosseous infusion: flow rates and utility. Ann Emerg Med 1999;34(4). 66 Tiffany BR, Adams J, Pollack CV et al. Prehospital use of a sternal intraosseous infusion device. Ann Emerg Med 1999;34(4). 67 Johnson DL, Findlay LM, Stair TO, Robinson DJ. Device for fast field intraosseous infusion via the adult manubrium. Ann Emerg Med 1998;32(3). 68 Curran A, Sen A. Bone injection gun placement of intraosseous needles. Emerg Med J 2005;22:366. 69 Schwartz D, Amir L, Dichter R, Figenberg Z. The use of a powered device for intraosseous drug and fluid administration in a national EMS: A 4-year experience. J Trauma Injury Infect Critic Care 2008;64(3);650–655. 70 David J-S, Dubien P-Y, Capel O, Peguet O, Gueugniaud P-Y. Intraosseous infusion using the bone injection gun in the prehospital setting. Resuscitation 2009;80:384. 269



Chapter 14 Needle thoracocentesis Content Definitions 272 The literature surrounding needle thoracocentesis 273 Equipment 274 Indications for use 274 Contraindications for use 274 Potential problems of use 275 Procedures for needle thoracocentesis 275 Chapter key points 276 References and Further reading 277 271

Chapter 14 Needle thoracocentesis Needle thoracocentesis is a life-saving procedure that will rarely be used in prehos- pital care, but it may prove of significant value when it is indicated. The technique is only a temporary measure but it may ‘buy’ extra time to convey the patient to more definitive care or bring the definitive care to the patient. Definitions Needle thoracocentesis involves placing a wide-bore cannula into the mid-clavicular line of the second intercostal space, just above the third rib, in order to decompress a tension pneumothorax.1 Normally, the pleural cavity is a potential space that is free from air and contains only a thin layer of fluid. When air enters the pleural cavity it is termed a pneumothorax.2 Tension pneumothorax is a life-threatening condition that occurs when the intrapleural pressure exceeds atmospheric pressure. It is created when injury to the chest or respiratory structures allows air to enter but not to leave the pleural space, resulting in a rapid increase in pressure on the affected side. This causes collapse of the affected lung, compression atelactasis of the unaf- fected lung, mediastinal shift towards the opposite side of the chest, and compres- sion of the vena cava.2 Resuscitation and trauma usually illustrate a patient in extremis and suggest that the clinical diagnosis is straightforward and that needle chest decompression always produces a rapid and reliable response.3,4 This may be far removed from the real life situation, where the classically taught signs are not often present. Table 14.1 sum- marises the symptoms and signs that may be useful for diagnosing tension pneu- mothorax in awake and ventilated patients.5 You are at the scene of a Road Traffic Collision along with the police and fire service. How will you manage the noise at the scene to maximise your chances of identifying a life-threatening thoracic injury? 272

Needle thoracocentesis Chapter 14 Table 14.1 Symptoms and signs of tension pneumothorax, adapted from Leigh-Smith and Harris (2005)5 Diagnosis of tension pneumothorax in Diagnosis of tension pneumothorax in awake patients ventilated patients Reliable and early Rapid disease progression Reliable and early • Pleuritic chest pain • Air hunger • Decrease in SpO2 – immediate • Respiratory distress • Decrease in BP • Tachypnoea • Tachycardia • Tachycardia • Falling SpO2 Others • Agitation • Increased ventilation pressure Disease lateralisation – ipsilateral • Surgical emphysema • Hyper-expansion Disease lateralisation • Hypo-mobility • Hyper-resonance • Ipsilateral • Decreased breath sounds • Hyper-resonance • Added sounds—crackles/wheeze • Decreased breath sounds • Chest hyper-expansion Disease lateralisation – contralateral • Chest hypo-mobility • Added sounds • Hyper-mobility Inconsistent Pre-terminal • Cyanosis • Decreasing respiratory rate • Distended neck veins • Hypotension • Tracheal deviation • Decreasing SpO2 • Decreasing level consciousness Inconsistent • Tracheal deviation • Distended neck veins The literature surrounding needle thoracocentesis The actual incidence of tension pneumothorax is not known, but it is more common in ventilated than awake patients and possibly most common in ventilated patients with visceral pleural injury from chest trauma.4 Emergency needle decompression is widely advocated for use in the emergency management of tension pneumotho- rax6,7,8 but there needs to be an appreciation of the potential problems associated with the technique; these will be discussed later. Needle thoracocentesis is often ineffective on its own and requires subsequent tube thoracostomy,9–14 hence why it should be seen as a temporary measure at best. There are also a number of factors that could cause needle decompression to fail; these include: 273

Chapter 14 Needle thoracocentesis Needle too short15,16,17 The recommended point for insertion of a needle is between the 2nd and 3rd inter- costal space in the mid-clavicular line. Whilst this is easy to access, it does entail penetration of pectoral muscles and a variable quantity of subcutaneous tissue, which may be increased by oedema and subcutaneous emphysema. It has previously been recommended that the minimum length should be 4.5 cm (standard length 14- gauge cannula);17 although up to one third of trauma patients have a chest wall thickness greater than 5 cm at the normal insertion point.18,19 A potential option is to use the 4th or 5th intercostal space in the midaxillary line and this has been recommended by ATLS as it contains less fat and avoids large muscles.4 Unfortunately this site may have an increased risk of lung damage in the supine patient, as gas collects at the highest point and adhesions are most likely in more dependent parts of the lung.20 Obstruction5,11 • Kinking of the catheter • Blood • Pleural fluid • Tissue. Malposition • Incorrect identification of landmarks; could lead to cardiac tamponade • Inadvertent removal by patient • Catheter too small to drain a large area5 • Missing a localised tension pneumothorax. Despite these problems, needle decompression is a technique that has proved safe and therapeutic in the prehospital environment,12,21–23 and leads to shorter on-scene times compared with tube thoracostomy.23 Equipment • 14-gauge cannula • 10 mL syringe (consider filling with sterile saline) • Alcohol swab • Asherman seal or other method of stabilising and securing the cannula. Indications for use When there are convincing signs of a tension pneumothorax (Table 14.1). Contraindications for use None in the emergency management of tension pneumothorax. 274

Needle thoracocentesis Chapter 14 Potential problems of use Problem Solution 1. Obstruction of catheter: Try to aspirate, if unsuccessful, insert second blood, fluid or tissue, needle close to original site. or kinked catheter. 2. Needle too short. Consider using 4th or 5th intercostal space in the 3. Malposition midaxillary line if authorised to do so. Leave in situ and secure. A small pneumothorax 4. Displaced cannula may be created by incorrect thoracocentesis, but this is unlikely to be a significant problem. However, if surgery and ventilation are required under anaesthesia, this can be expanded to a tension pneumothorax. If cannula has been removed, cover wound with sterile dressing and notify receiving hospital. Insert a second cannula and secure well. Box 14.1 Potential problems of needle thoracocentesis There are a number of other potential problems associated with needle thoracocen- tesis, most of which the paramedic can do little about in the field (Box 14.2). Unnecessary pain/discomfort for the patient if procedure was not required Pneumothorax with potential to tension later – especially if ventilated Cardiac tamponade Life threatening haemorrhage Intrapleural haematoma Atelactasis Pneumonia Box 14.2 Morbidity associated with needle decompression5 Procedures for needle thoracocentesis Procedure Additional information/rationale 1. Ensure a patent airway and adequate oxygenation. 2. Ensure adequate ventilation Maintains oxygenation 3. Expose the chest. Ensures adequacy of ventilation. Necessary to identify landmarks and perform technique. 275

Chapter 14 Needle thoracocentesis Procedure Additional information/rationale 4. Identify landmarks (Figure 14.1): The mid-clavicular line avoids the internal mammary arteries. • Locate suprasternal notch and move fingers down Nerves, arteries and veins pass manubrium to the angle of Louis (this sits level with just below each rib so insertion point should be the superior the second rib). margin of the third rib. • From angle of Louis, identify second intercostal space in the mid-clavicular line on the affected side. • Insertion should be on the superior border of the third rib. 5. Clean the skin using alcohol wipe. Reduces the risk of infection. 6. Remove the flashback chamber from a 10–16 g cannula and attach a 10–20 mL syringe. 7. Insert needle fully at 90° to the skin. Withdraw on Free flow of air demonstrates that the plunger of the syringe until a free flow of air lung tissue has been reached. enters the syringe. 8. Advance cannula and remove needle and syringe to A rush of air signifies that the allow a rush of air out of the syringe. diagnosis was correct. 9. Secure cannula in place to prevent dislodgement. Improper placement or movement may cause damage to other organs or structures. 10. There is no need to re-fit the cannula cap and time should not be wasted in applying a one-way valve. 11. Complete documentation Chapter Key Points 1. Needle thoracocentesis is a potentially life-saving technique. 2. Diagnosis of tension pneumothorax may be difficult in the prehospital environment. 3. Many of the commonly taught signs and symptoms may not be present or may be unreliable indicators. 4. There are a number of potential problems related to needle thoracocentesis, some of which the paramedic may be able to manage, some may not be manageable in the field. 276

5 Needle thoracocentesis Chapter 14 12 Thoracic outlet (inlet) 4 First rib Clavicle Suprasternal notch Manubrium Third rib Body of sternum Intercostal space Xiphisternum Costal cartilage Costal margin 3 1 Costochondral joint Floating ribs 2 Sternocostal joint 3 Interchondral joint 4 Xiphisternal joint 5 Manubriosternal joint (angle of Louis) Figure 14.1 Sternal landmarks for needle thoracocentesis. Reproduced from Faiz O, Moffat D. Anatomy at a Glance, 2nd edn, copyright 2006, with permission of Blackwell Publishing. References and Further reading 1 Ferrie EP, Collum N, McGovern S. The right place in the right space? Awareness of site for needle thoracocentesis. Emerg Med J 2005;22:788–789. 2 Porth CM. Pathophysiology, Concepts of Altered Health States, 7th edn. Philadelphia: LWW, 2005. 3 ALSG. Advanced Life Support Manual, 4th edn. London: Resuscitation Council (UK), 2001. 4 ATLS. Advanced Trauma Life Support. 6th edn. Chicago: American College of Surgeons, 1997. 5 Leigh-Smith S, Harris T. Tension pneumothorax – time for a re-think? Emerg Med J 2005;22;8–16. 6 Joint Royal Colleges Ambulance Liaison Committee. UK Ambulance Service Clinical Practice Guidelines version 4. London: IHCD, 2006. 7 National Association of Emergency Medical Technicians in Co-operation with the Committee on Trauma of the American College of Surgeons. PHTLS Prehospital Trauma Life Support, 6th edn. Missouri: Mosby/JEMS, 2006. 277

Chapter 14 Needle thoracocentesis 8 Sanders M. Mosby’s Paramedic Textbook. Missouri: Mosby, 2006. 9 Britten S, Palmer SH. Chest wall thickness may limit adequate drainage of tension pneumo- thorax by needle thoracocentesis. J Accid Emerg Med 1996;13:426–427. 10 Britten S, Palmer SH, Snow TM. Needle thoracocentesis in tension pneumothorax: insuffi- cient cannula length and potential failure. Injury 1996;27:321–322. 11 Conces DJ Jr, Tarver RD, Gray WC et al. Treatment of pneumothoraces utilizing small caliber chest tubes. Chest 1988;94:55–57. 12 Cullinane DC, Morris JA Jr, Bass JG et al. Needle thoracostomy may not be indicated in the trauma patient. Injury 2001;32:749–752. 13 Jenkins C, Sudheer PS. Needle thoracocentesis fails to diagnose a large pneumothorax. Anaesthesia 2000;55:925–926. 14 Jones R, Hollingsworth J. Tension pneumothoraces not responding to needle thoracocen- tesis. Emerg Med J 2002;19:176–177. 15 American College of Surgeons, Committee on Trauma. Advanced Trauma Life Support Course Manual. Washington DC: ACS, 1997. 16 Britten S, Palmer SH. Chest wall thickness may limit adequate drainage of a tension pneu- mothorax by needle thoracocentesis. J Accid Emerg Med 1996;13:426–427. 17 Britten S, Palmer SH, Snow TM. Needle thoracocentesis in tension pneumothorax: insuffi- cient cannula length and potential failure. Injury 1996;27(5):321–322. 18 Marinaro J, Kenny C, Smith S et al. Needle thoracostomy in trauma patients: what catheter length is adequate? Acad Emerg Med 2003;10:495. 19 Zengerink I, Brink P, Laupland K. Needle thoracostomy in the treatment of a tension pneu- mothorax in trauma patients: what size needle? J Trauma 2008;64:111–114. 20 Goodman L, Putman C. Intensive Care Radiology Imaging of the Critically Ill, 2nd edn. Philadephia: W B Saunders, 1982:99–100. 21 Coats TJ, Wilson AW, Xeropotamous N. Pre-hospital management of patients with severe thoracic injury. Injury 1995;2:581–585. 22 Cameron PA, Flett K, Kaan E et al. Helicopter retrieval of primary trauma patients by a paramedic helicopter service. Aust NZ J Surg 1993;63:790–797. 23 Barton ED, Epperson M, Hoyt DB et al. Prehospital needle aspiration and tube thoracostomy in trauma victims: a six-year experience with aeromedical crews. J Emerg Med 1995;13:155– 163. 278

Chapter 15 Pain assessment and management Content Definitions 280 Acute pain v chronic pain 281 281 Assessing pain 287 Assessing pain in cognitively impaired patients 288 290 Overview of pain management techniques 291 Chapter key points References and Further reading 279

Chapter 15 Pain assessment and management Pain is one of the most frequent symptoms presented by patients in the emergency care setting,1–3 with a 2004 patient survey suggesting that 80% of patients experi- enced pain whilst in the ambulance.4 The ability to manage pain in emergency care is a key skill that provides comfort, minimises the stress associated with sudden illness or injury, and reduces the det- rimental psychological and physiological effects associated with pain. Despite this, numerous studies have shown that pain is managed sub-optimally in emergency care.5–9 A UK survey found that 1 in 5 patients were not satisfied with the way their pain was managed in the prehospital environment;4 this is likely to be an underesti- mation as patients often report high levels of satisfaction even though their pain level has actually increased.10 Definitions A widely used definition of pain is: ‘… an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage’.11 This definition does not address the autonomic responses associated with obnoxious stimuli, which is a key feature of pain in the emergency setting. A second definition proposed by Margo McCaffery as long ago as 1968 has become widely used by healthcare professionals. She states that pain is: ‘… whatever the experiencing person says it is, existing whenever the expe- riencing person says it does’.12 Pain is a complex phenomenon that comprises both physical and emotional ele- ments; it is a subjective experience and should rely heavily on the patient’s self- report whenever possible. A significant problem for the practitioner is related to this subjectivity. Paramedics interviewed by researchers expressed doubts as to the validity of some patients’ pain descriptions, suggesting that patients may feel they need to increase their explanation of pain to be believed and to be taken seriously by the paramedics. Others felt that pain descriptions were exaggerated by patients with minor ailments so that they can justify calling an ambulance, also thinking that they will be seen more promptly at hospital.13 The paramedics also believed that the cultural background of the patient had a major impact on their pain experience. They recognised a cultural difference to exist in the way that pain was expressed, with some cultures thought to be more vocal and emotional in expressing their pain. It was also held that older people may perceive pain differ- ently to younger people and would be less likely to ask for help.13 All of this indi- cates just how difficult assessment of pain can be, especially acute pain in the emergency setting. 280

Pain assessment and management Chapter 15 Acute pain v chronic pain Acute pain Acute pain has been defined in a number of different ways but a common feature in definitions is that is a symptom with a discernible cause and usually subsides when injured tissues heal. Acute pain has a protective function. Chronic pain Chronic pain is, by definition, pain that has persisted beyond the time of healing; a classification based purely on causal agent is not achievable. Some patients become extremely disabled and suffer intractable pain even though their identifiable pathol- ogy appears to be relatively mild; other individuals with similar pathologies may report pain but do not present with the same level of disability.14 Good evidence exists to show that quality of life for patients with chronic pain is more associated with beliefs about pain than the severity itself.15 Although emergency care is often associated with acute pain, it is likely that those suffering from chronic pain (e.g., cancer, lower back pain, multiple pain localisations) will also access the emergency services. The cornerstone of pain management is the assessment of the pain. A variety of pain assessment tools are available to assist in determining the level of pain and evaluating the effectiveness of interventions. These tools should be used in conjunc- tion with a thorough history of the pain to help diagnose the most likely cause of the pain as well as the severity. Assessing pain • Look at the patient • Taking the history of the pain • Pain assessment tools. Initial observations It is worth noting the patient’s position, any guarding of the site of pain and how well they mobilise. Significant information can also be obtained by watching the patient’s face, especially during mobilisation. This is covered later in the chapter as a checklist of non-verbal indicators. History of the pain The history is vital to help make a differential diagnosis and several mnemonics have been suggested to help practitioners. Whether or not to use a mnemonic is for the individual practitioner to decide; two different ones will be presented here. It is important to remember that questions are only relevant if the practitioner under- stands the answers, so it is essential to have a sound understanding of the patho- physiology behind the clinical manifestations. 281

Chapter 15 Pain assessment and management OPQRST mnemonic This is probably one of the most commonly taught mnemonics in emergency care although some texts do not mention the ‘O’ element. O Onset P Provocation/palliation Q Quality R Region/radiation S Severity T Timing O Onset Did the problem develop suddenly or more gradually? What was the patient doing when the pain came on? Was the patient exercising or exerting themselves? Was the patient eating or drinking, if so, what? P Provocation/palliation What provokes the pain (makes it worse)? What palliates the pain (makes it better?) Were there any precipitating factors e.g., did this come on after exercise? Q Quality What does it feel like, e.g., sharp, dull, stabbing, burning or crushing? Allow the patient to describe their pain otherwise they may say what they think you want them to say. Use their descriptors on the case report form. R Region/radiation Where is the pain? Does the pain stay in one place? Does it go anywhere else? Ask the patient to point to the pain – can it be localised or is it diffuse? If the pain radiates, where does it go? Did the pain start elsewhere but become localised in one place? S Severity/associated symptoms How bad is the pain? (See section below on pain assessment tools) Are there any associated symptoms – e.g., nausea, vomiting, dizziness? T Time/temporal relations When did the pain start? How long did it last? Is it constant or intermittent? How long has it been affecting your patient for? (It may have been going on for some time) 282

Pain assessment and management Chapter 15 Table 15.1 CHESTPAIN mnemonic C Commenced when? When did the pain start? Was onset associated with anything specific? Exertion? Activity? Emotional upset? H History/risk factors Do you have a history of heart disease? Is there a primary relative (parent/sibling) with early onset and/or early death related to heart disease? Do you have other risk factors, e.g., diabetes, smoking, hypertension, or obesity? E Extra symptoms What else are you feeling with the pain? Are you nervous? Sweating? Is your heart racing? Are you short of breath? Do you feel nauseous? Dizzy? Weak? S Stays/radiates Does the pain stay in one place? Does it radiate or go anywhere else in the body? Where? T Timing How long does the pain last? How long has this episode lasted? How many minutes? Is the pain continuous or does it come and go? When did it become continuous? P Place Where is your pain? Check for point tenderness with palpation. A Alleviates What makes the pain better? Rest? Changing position? Deep breathing? Aggravates What makes the pain worse? Exercise? Deep breathing? Changing positions? I Intensity How intense is the pain? N Nature Describe the pain (do not suggest descriptors) Adapted from Newberry, Barnett and Ballard (2003).16 A recent mnemonic has been proposed specifically for the evaluation of chest pain (Table 15.1) and incorporates risk factors for cardiac problems. The mnemonic is CHESTPAIN. Using the mnemonics – what answers would help you to differentiate acute myocardial infarction from acute angina? Pain assessment tools The tools that will be covered in this section include: • Numerical Rating Scale • Visual Analogue Scale • Verbal Rating Scale • Wong–Baker FACES Pain Scale • Checklist of non-verbal indicators. 283

Chapter 15 Pain assessment and management Numerical Rating Scale (NRS) The numerical rating scale is probably the most commonly used tool in prehospital emergency care and generally encompasses an 11 point scale ranging from 0 (no pain) to 10 (worst pain). It is simple to administer and requires no specific equipment. The NRS is often administered verbally in the prehospital setting but it could easily be completed as a paper exercise (see Figure 15.1), which may be helpful to those patients who have difficulty in allocating a pain score verbally. A study showed the NRS to have poor reproducibility17 and highlighted the importance of consistency of terminology to ensure that confusion does not arise. A study in the emergency department has shown a verbally administered NRS to be a suitable substitute for the VAS, see below in the assessment of acute pain.18 Procedure Additional information/rationale 1. Establish that the patient is able to use Improves likelihood of answers being numbers to quantify their pain. accurate. 2. Explain the parameters of the scale and use Patient needs to know which end of the descriptors at each end of the scale. scale represents severe pain for accuracy of measurement. 3. Ask the patient one of the following questions: • What number would you give your pain right now? • What number on a 0 to 10 scale would you give your pain when it is the worst that it gets and when it is the best that it gets? • At what number is the pain at an accept- able level for you? 4. Record pain score and repeat at frequent Allows evaluation of effectiveness intervals. of pain management strategies and whether more needs to be done. 5. For written NRS, follow the above but ask patient to circle the number that describes how much pain they are having. No pain Worst Imaginable pain 0 1 2 3 4 5 6 7 8 9 10 Figure 15.1 Numerical Rating Scale. 284